A generic device of the pre-cited type is known from U.S. Pat. No. 4,858,572. In a preferred embodiment of this device, six equally large working chambers are formed in the hollow space of the drive pinion between six circumferentially opposed intermediate walls. These six working chambers are divided into fluid-tight first and second pressure chambers by six wings rigidly connected to the hub of a winged wheel which is connected to the camshaft. The mechanical coupling between the winged wheel and the drive pinion of the device is accomplished by a spring-loaded locking pin arranged in a radial bore of one of the intermediate walls. This locking pin engages a reception bore arranged between two wings in the hub when the wings of the winged wheel abut in an end position against the intermediate walls of the drive pinion and the first pressure chambers of the device are cut off from the pressurization by the hydraulic pressure medium. When, upon a renewed pressurization of these pressure chambers, the hydraulic medium pressure exceeds a set value, the locking pin is displaced against the force of its spring entirely out of the reception bore in the hub into the radial bore in the intermediate wall so that the mechanical coupling between the winged wheel and the drive pinion is released. When, after a relative rotation between the winged wheel and the drive pinion, the wings are brought into abutment in their opposite end position against the intermediate walls of the drive pinion, and the second pressure chambers of the device are cut off from the pressurization by the hydraulic pressure medium, a second mechanical coupling between the winged wheel and the drive pinion is effected by a locking pin similarly arranged in another intermediate wall. This locking action is likewise undone when a defined pressure medium pressure in the second pressure chambers is exceeded.
A mechanical coupling of this type between the winged wheel and the drive pinion, however, has the drawback that it is formed by a plurality of additional separate components which in view of the extra expenses for their fabrication and assembly disadvantageously increase the manufacturing costs of such a vane-type adjusting device. Also, due to the configuration of the locking pins as simple pressure pins, there exists the possible drawback that the locking pins be deformed when they have been subject to high stresses acting in both directions of rotation so that a continued, satisfactory locking of the device is then not always guaranteed.